• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.102-108
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• 2009

Fossil power plants firing lower grade coals or equipped with modified system for NOx controls are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. In order to develop a on-line combustion tuning system, field test was conducted at operating power boiler. During the field test the exhaust gases' $O_2$, NOx and CO was monitored by using a spatially distributed monitoring grid located in the boiler's high temperature vestibule and upper convective back-pass region. At these locations, the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. using these monitored information we can improving combustion at every point within the furnace, therefore the boiler can operate at reduced excess $O_2$ and gas temperature deviation, reduced furnace exit gas temperature levels while also reducing localized hot spots, corrosive gas conditions, slag or clinker formation and UBC. Benefits include improving efficiency, reducing NOx emissions, increasing output and maximizing availability. Discussion concerning the reduction of greenhouse gases is prevalent in the world. When taking a practical approach to addressing this problem, the best way and short-term solution to reduce greenhouse gases on coal-fired power plants is to improve efficiency. From this point of view the real time optimized combustion tuning approach is the most effective and implemented with minimal cost.

• 한국어류학회지
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• 제11권2호
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• pp.126-133
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• 1999

무지개송어 (Oncorhynchus mykiss), 메기 (Silurus asotus) 그리고 미꾸리 (Misgurnus anguillicaudatus)의 성숙 난자의 방사대 (zona radiata) 및 난문의 미세구조적 특징을 광학, 주사 및 투과 전자현미경을 이용하여 조사하였다. 무지개송어와 메기의 난에 있는 난문은 깔대기 형태의 전정과 방사대를 통과하는 끝이 작아지는 통로로 구성되어 있었다. 무지개송어와 메기의 난문은 편평한 구멍과 긴 통로로 구성된 구조를 나타내었다. 메기 난문의 구조는 무지개송어 난문의 구조와 일치되었다. 무지개송어의 난문을 구성하는 내부 벽은 시계방향(우선형)의 구조를 나타내었다. 미꾸리의 난문은 짧은 통로를 지닌 얕은 구멍을 가진 형태를 나타내었고, 시계방향의 반대방향으로 난문의 벽은 방향성율 나타내었다. 미꾸리의 이러한 나선형의 방향은 무지개송어의 방향과 일치하지 않는 것으로 나타내었다. 개구부 바로 주변부에 있는 표면은 실험에 이용된 3가지 어류에서 모두 여러 가지 크기의 작은 구멍이 존재하였다. 상호 연결부위 (ridge)가 모든 어류의 미수정된 난자에서 관찰되었다. 본 논문에서는 난성숙시 난막과 난문의 형태를 알아보기 위해서 3가지 양식어종 난자의 표면형태와 난문의 미세구조를 상호 비교하였다.

• 대한치과보철학회지
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• 제44권6호
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• pp.712-721
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• 2006

Statement of problem. Acrylic resin is most commonly used for denture bases. However, acrylic resin has week points of volumetric shrinkage during polymerization that reduces denture fit. The expandability of POSS (Polyhedral Oligomeric Silsesquioxane) containing polymer could be expected to reduce the polymerization shrinkage of denture bases and would increase the adaptability of the denture to the tissue. Purpose. The purpose of this study was to compare the dimensional stability in the conventional acrylic resin base, POSS-containing acrylic resin base, and metal bases. Materials and methods. Thirty six maxillary edentulous casts and dentures of different base were fabricated. Tooth movement and tissue contour change of denture after processing (resin curing, deflasking, decasting and finishing without polishing) and immersion in artificial saliva at $37^{\circ}C$ for 1 week and 4 weeks were measured using digital measuring microscope and threedimensional laser scanner. Results. The results were as follows: 1. The conventional resin group showed significant (p<0.01) dimensional change throughout the procedure (processing and immersion in artificial saliva). 2. After processing, the metal group and POSS resin group showed lower linear and 3-dimensional change than conventional resin group (p<0.01). 3. There was no statistically significant linear and 3-dimensional change after immersion for 1 week and 4 weeks in metal and POSS resin group. 4. In all groups, the midline and alveolar ridge crest area presented smaller 3-dimensional change compared with vestibule and posterior palatal seal area after processing and soaking in artificial saliva for 1 week and 4 weeks (p<0.01). Conclusion. In this study, a reinforced acrylic-based resin with POSS showed good dimensional stability.

• 대한두개안면성형외과학회지
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• 제19권2호
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• pp.148-151
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• 2018

The nose is an important landmark of the face and its shape and beauty is of significant concern. The columella is the subunit between the two nostrils that provides support and projection to the nasal tip and has functional role in nostrils, as well as aesthetic. Ethiology for columellar absence or deficiency is diverse, and it is one of the most complex nasal subunits to reconstruct because of its narrow horizontal dimension, its tenuous vascularity and limited availability of adjacent tissue. We present a patient with columellar, membranous septum and upper lip defect, due to oncological resection. The lip reconstruction was designed using advancement of two upper lip edges with the technique of webster perialar/nasocheek advancement. However, the perialar/nasocheek tissue which is usually discarded was used as inferiorly based skin flaps to reconstruct the membranous septum, columellar skin and nasal vestibule lining. Rib cage cartilage graft was used as columellar strut for support. At 1-year follow-up, the patient has good nasal contour and projection. Scaring of the columella is very subtle. This is a versatile way for successful reconstruction of a columella and large central facial defect in one-stage operation. It is a method which provides very satisfactory aesthetic result with minimum patient morbidity and discomfort.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권6호
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• pp.530-534
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• 2011

This paper reports two cases of schwannomas arising from the oral cavity. One is an intraoral ancient schwannoma located at the left cheek, which evolved over a period of 13 years. The tumor was a well-demarcated buccal mass, which was located in the left lower first premolar area, with an obliterated the buccal vestibule, leaving the overlying mucosa intact. The second case was a central intraosseous schwannoma located from the left lower 1st molar periapical area to the left 3rd molar periapical area. Pathologically, the first mass was composed of the spindle shaped tumor cells with wavy nuclei beneath the fibroconnective tissue of the gingiva but second case mass was not. Occasional nuclear pleomorphism was observed but mitosis or necrosis was absent. There were Antoni A and B areas along with strong, diffuse staining with the S-100 protein. Ancient schwannomas were diagnosed. Schwannoma is a slow-growing benign tumor, and an ancient schwannoma that shows cellular atypism is a variant of a schwannoma caused by purely degenerative changes. To date, only limited cases of ancient schwannomas in the oral cavity have been reported.

• 대한치과보철학회지
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• 제53권3호
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• pp.215-221
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• 2015

심한 마모를 가진 환자의 치료에서 광범위한 보철 수복을 필요로 하는 경우가 있는데, 마모의 원인과 수직 고경의 변화 유무 등을 판단하여 현재 구강상태의 회복과 장기간의 안정성을 이루어야 한다. 수직 고경을 증가시킬 때는 임시 수복을 하고 장기간의 관찰을 통해 환자의 적응을 평가해야 한다. 본 증례의 환자54세 남자 환자로 전반적인 치아 마모와 심미적 불만족을 주소로 내원하였다. 환자의 구강 내 소견 상 교모와 부식이 동반되어 과도한 마모가 발생한 것으로 진단하였다. 수직 고경의 변화를 평가하기 위해 안정위시 악간공극, 발음, 안모, 심미, 임상적 치관 길이, 중절치 절단과 순측 전정과의 수직거리 등을 평가하였고, 교합기의 incisal pin기준으로 수직 고경을 2.5 mm 증가하기로 하였다. 임시 보철물을 이용하여 8주의 안정화 기간 이후 최종 보철물을 제작하였다. 6개월 간 경과 관찰 결과 기능적, 심미적으로 양호한 결과를 보였다.

• 한국태양에너지학회 논문집
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• 제29권5호
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• pp.45-52
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• 2009

Fossil power plants firing lower grade coals or equipped with modified system for $NO_x$ controls are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. In order to develop a on-line combustion tuning system, field test was conducted at operating power boiler. During the field test the exhaust gases' $O_2,\;NO_x$ and CO was monitored by using a spatially distributed monitoring grid located in the boiler's high temperature vestibule and upper convective rear pass region. At these locations, the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. using these monitored information we can improving combustion at every point within the furnace, therefore the boiler can operate at reduced excess $O_2$ and gas temperature deviation, reduced furnace exit gas temperature levels while also reducing localized hot spots, corrosive gas conditions, slag or clinker formation and UBC. Benefits include improving efficiency, reducing $NO_x$ emissions, increasing output and maximizing availability. Discussion concerning the reduction of greenhouse gases is prevalent in the world. When taking a practical approach to addressing this problem, the best way and short-term solution to reduce greenhouse gases on coal-fired power plants is to improve efficiency. From this point of view the real time optimized combustion tuning approach is the most effective and implemented with minimal cost.

• Archives of Plastic Surgery
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• 제38권3호
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• pp.333-337
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• 2011

Purpose: Various operations have been proposed to compensate for congenital absence of the vagina using ileal or colonic interposition. These methods involve laparotomy, which shows postoperative complications such as long scar and delayed recovery. One case of neovagina reconstruction with laparoscopic rectosigmoid colpopoiesis in Mayer-Rokitansky-Kuster-Hauser syndrome is presented to avoid laparotomic complications. Methods: Laparoscopic surgery was performed in a 27-year-old MRKH syndrome patient. After a cruciate incision, blunt dissection through two-finger wide space was created between the bladder and the rectum. A 14-cm rectosigmoid segment vascularized by a branch of sigmoid artery was isolated by laparoscopy. The distal end was sutured with vaginal vestibule mucosa. A continuity of intestine was restored by circular end-to-end proximate curved intraluminal stapler CDH29$^{(R)}$ through perineal opening. Results: Total operation time was 4 hr 15 min. Normal walking and ingestion were possible within 3 days and 4 days after surgery. The hospital stay was 7 days and the patient was followed up for 6 months. The neovaginal introitus was wide enough for inserting two fingers, and there has been no narrowing of the neovagina on palpation as confirmed by vaginogram. The patient had functional self-lubricating neovagina without excessive mucous production or the need for routine dilation or unnoticeable scar. Conclusion: The successful result of this laparoscopic vaginal reconstruction technique with rectosigmoid segment suggests that this technique can be considered for the option of vaginal reconstruction in girls with the MRKH syndrome.

• 대한한방내과학회지
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• 제21권1호
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• pp.181-184
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• 2000

Dizziness is one of common diseases clinically, it is defined as a hallucination or an illusion of motion that causes sensation disorder of circumstance, and described as circulatory. rotatory leaning. shaking sensation. In particular, benign paroximal positional vertigo(BPPV) is one of peripheral vertigo, it causes dizziness due to debris which has collected within a part of the inner ear. Chemically, debris are small crystals of calcium carbonate. They are derived from structures in the ear called 'otoliths' that have been damaged by head injury, infection, or other disorder of the inner ear, or degenerated because of advanced age. The symptoms of BPPV include dizziness or vertigo, lightheadedness, imbalance, and nausea, Activities which bring on symptoms will vary in each person, but symptom are almost always precipitated by a position change of the head or body. As for treatment of vertigo, it is differentiated as excess in the upper and deficiency in the lower(上實下虛) and treated in oriental medicine and are used to stability. antihistaminics . anticolinergics . vestibule control drug of GABA system in western medicine. Moreover, Dix-hallpike maneuver is applicated in diagnosis and treatment of BPPV patients. A case of dizziness patient suggested benign paroximal positional vertigo who is diagnosed as weakly dizziness(虛暈)showed prominent improvement by Jaeumkunbitang-gamibang(滋陰建脾湯) and Dix-hallpike maneuver.

• 한국화재소방학회논문지
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• 제30권4호
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• pp.6-13
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• 2016

건축물에서의 연기제어 시스템과 관련하여 국내에서는 거실에 대한 배연기준과 피난계단 및 부속실에 대한 제연기준이 제시되고 있으나, 대형화 고층화 복합화 되어가는 첨단 건축물에 대한 적용성을 검토하면 국내 설계기준에 따른 연기제어 시스템은 화재시 연기안전을 확보하기 곤란할 수 있다. 따라서 대형 고층 복합의 첨단 건축물에 대한 화재시 연기안전성을 높이고 화재와 건축물 특성에 따른 상호 연기제어 연계성 확보와 통합적 설계가 가능한 성능위주 연기제어의 적용이 요구된다. 본 논문에서는 국내 연기제어 기준을 분석하고 개선이 필요한 부분을 제시하였으며, 선진외국에서의 성능위주 설계 수행에 대한 법체계와 성능위주 연기제어 설계의 지침을 조사하고 분석하였다.